The purpose of this research is to determine the size, detergent binding and subunit composition of the insulin receptor from rat adipocytes, rat hepatocytes, and turkey erythrocytes before and after purification. The mechanism of coupling between the insulin receptor and the (Na ion, K ion) ATPase will be studied by examination of the coupling system in normal and in fused cells, and by reconstitution of the components in artificial lipid vesicles.